Art of feeding finely comminuted fuel into a combustion chamber



C. M. BUCK Dec. 20, 1932.

ART OF FE EDING FINELY COMMINUTED FUEL INTO A COMBUSTION CHAMBER Filed May 10, 1928 2o zmi m ,5 I: v L18 Patented Dec. 20, 1932 UNITED STATES PATENT oar-lea CHARLES H. BUCK, F BROOKLYN, NEW YORK ART OF FEEDING FINELY COMMINUTED FUEL INTO A COMBUSTION CHAMBER Application filed Kay 10, 1928. Serial No. 278,523.

My invention relates to an improvement in Figures 7 and 8 are details of the air port the art of feeding finely comminuted fuel shutter control. into a combustion chamber, and its novelty In the drawing 10 is a fuel container havconsists in the steps of the process and the ing a fuel feed pipell and an air inlet pipe means for carrying out the same as will be 12. The fuel contalner terminates at its more fully hereinafterpointed out. lower end in an agitator housing 13 in which My process and the means for carrying out 1s mounted an agitator 14 on a shaft 15 and the same are particularly adapted for use in wh ch has alternately staggered rows of connection with the products of my pending pyramidal agitating members 16 rigidly 10 United States patent application Serial No. mounted thereon. A gate 17 having air open- 265,303,filed March 28, 1928 on my improveings 18 is mounted immediately below an ment in the treatment of coal and other carbo- Opening 19 at the base of the agitator 11 L18- naceous material of a similar nature and in ing 13 and the gate 17 has toothed lugs 29 the product produced, but it is also adapted adapted to be meshed by gears 21 mounted to be used in connection with pulverized coal on shaft 22 which is adapted to be turned or or fuel prepared by other methods. controlled by a wheel or handle 23 rigidly In the previous methods and means for mounted on said shaft 22. A blower cylinfeeding finely comminuted fuel to a combusder 24 is mounted immediately below the tion chamber it has been necessary to use an exgate 17 and in the same is mounted a rotatcess of air and a substantially high pressure ing blower 25 of usual construction which is m with the result that the flame in the combusrotated on shaft 26. On the shaft 26 are tion chamber varies substantially a large mounted apair of hanger members 27 and amount of the fuel is not consumed but is 27a between which is suspended air port wasted and the combustion chamber is exces- Shutters 28 by means of which the opening A sively heated at certain points so that there is to the blower cylinder 24 may be varied as a very substantial loss of heat released and th desired. A passageway 29 the full width of attendant destruction of the fire chamber. the gate 17 and the opening 19 leads from My process and the means for carrying out the blower cylinder 24:, gate 17 and opening the same overcome all of these difliculties, fur- 19 into the combustion chamber which is not nishing substantially perfect aeration to the h wn, Where the fuel is to be consumed. so comminuted fuel and conveying the same on On one end of the blower shaft 26 is mountalight current of air spread out in a sheet and ed a [pulley 30 adapted to be connected up delivered to the combustion chamber in a by a Bi t the Source of power not shown. sheet the full width of the combustion space, A g 31 is igid y c red to he Shaft 26 thereby insuring greatly improved combusf a large gear 32 is rigidly Secured to an 85 tion and consumption of the fuel and absorpldler Shaft 33 so that said gears 32 and 31 tion of the heat released without any injury mesh and run together- A Small 34 to the fire Chamber or loss of fueL is also rigidly secured on the idler s aftfi ii w Referring to the drawing, Figure 1 is a i t meshes wlth a large g 35 Whlch ls front elevation of my device rigidly secured on the agitator shaft 15. 99 hFigure 2 is aFvertical cross section through ggs g s f g g :5 2 32 5 2 te middle of igure 1.

of which the ad ustment of the air ort shutan end new of the agltator' ters 28 may be adjusted manually a s desired. s ig'ure 4 1s a fragment of one end of the In Operating m devica the fine} com 5 ag tator, parts being broken away for conb y w y Y minuted or pulverized fuel which is fed FF }1111$tmt10nthrough pipe 11 into the container 10 passes iguro 1 :1 fr I1 W f the g t down through 10 into the agitator housin Figure 6 lsan end view of the same looking 13. The agitator 14, by means of the agitat- 00 in from the right-hand end of Figure 5. ing members 16 which pick up and carry 1% complete width of the opening 19 and passageway 29 so that the induced air carries this portion, spreading it in a thin sheet along through the passageway 29 where the air from the blower 25 comes in to carry it along at a slightly more rapid rate, tumbling it and mixing it so that it is thoroughly aerated and delivering it in a suspended sheet to the combustion chamber. I

As the blower 25 is rotated by, means of the pulley 30, the gear 31 meshing with gear 32 drives the gear 32 and the idler shaft 33 so that gear 34 is also rotated thereby and being in mesh with gear 35 rotates the same whereby the shaft 15 is rotated thereby rotating the agitator 14 as described.

In carrying out my method of feeding finely comminuted fuel to a combustion chamber the comminuted fuel is fed across the complete width of the conveyor passageway, being picked up by a current of induced air and spread substantially into a sheet whereby it is carried into the column of blown air still in a sheet and as it is so carried through the conveyor passageway through tumbling and contact with the surfaces of the side of the conveyor passageway is aerated and fed into a combustion chamber substantially in a sheet and the full width of the combustion chamber and being aerated is combustible as fed, the air pressure, not being sufficient to prevent the aerated comminuted fuel from having time to thoroughly combust in the combustion chamber.

By drawing or removing fuel from the.

container or source of supply spread out in the form of a sheet or approximately in the form of a sheet into a current of air of approximately the same width the fuel is approximately spread out in a uniform thin sheet as it enters the induced air current and this condition is not disturbed by the blower air current which is merely sufiieient to continue the further carrying of the sheet of fuel thoroughly mixed with air to the combustion chamber. The air current is regulated so as to contain such quantities of air as will furnish the necessary oxygen for the thorough combustion of the fuel and the regulation of the air current may be by the carbon dioxide content of the stack gases or by the products of combustion. The delivery of the comminuted fuel into the induced air current spread out in the form of a sheet and the maintaining of this sheet for the entire width of the conveyor passageway right into the full width of the combustion chamber insures thorough aeration and suspension during the entire combustion of the fuel. This avoids the use of excess air for the driving or carrying of the comminuted fuel and permits the combustion to take place under less pressure than has been possible heretofore and the heat released is permitted to tarry longer whereby it is chiefly absorbed and utilized instead of being blown on through the combustion chamber and up the stack.

The delivery of the comminuted fuel in an approximately uniform sheet into the entire width of the combustion space insures uniform combustion across the entire width of said combustion space thereby securing the releasing of the heat uniformly across the entire combustion chamber which permits of themaximum absorption of said heat.

My method of feeding the comminuted fuel in a sheet the entire width of the combustion chamber permits of the withdrawing of the fuel from the container in. the desired quantity varying from a mere film to a fraction of an inch in thickness. Any slight variation in the thickness of the fuel is at once reflected in its combustion. This permits of the most positive and exact regulation of the fuel drawn or removed from the container to meet the heat requirements. It is thus seen that the feeding of the fuel may be properly regulated by a thermostat or through steam pressure or through any other well known heat control method. The quantity of fuel drawn from the container is made to vary to correspond with the variations in the load or amount of heat required whereby perfect feed control is attained and maintained.

I do not limit myself to the particular means disclosed as any equivalent means for carrying out the method described may be used to attain the result described.

'More nearly perfect results will be secured in carrying out my process if the finely comminuted and suspensive fuel described in my pending application Serial No. 265,303 is used, but my method and means for carrying out the same may be also successfully used with any good quality of pulverized coal or finely comminuted fuel.

The method of burning pulverized coal mixed with the air required for combustion is part of the subject matter of my copending application Serial No. 629,063, filed August Laeneae erally extending conduit into the upper part or which the orifice opens at a point intermediate the ends thereof, burner at one end of the conduit, means for supplying a blast of air into the opposite end of the conduit in the lower part thereof, a passage in the upper part of said conduit at said opposite end thereof, said passage being open to the atmosphere at one end and having its op 0- site discharge end in proximity to said ori ce, whereby the said blast of air draws a current of air through said passage which current of air moves past said orifice and between it and the blast of air, and the coal, under the influence of gravity and suction, drops into a stream of air of double strata, one stratum 01" which moves more slowly than the other, so that mixing occurs in the conduit.

3. In combination, a pulveriaed coal hopper having a bottom discharge orifice, a laterally extending conduit into the upper part of which the orifice opens at a point intermediate the ends thereof, a burner at one end of the conduit, means for supplying a blast of air into the opposite end of the conduit in the lower part thereof, a passage in the upper part of said conduit at said opposite end thereof, said passage being open to the atmosphere at oneend and having its opposite discharge end in proximity to said orifice, whereby the said blast of air draws a current of air through said passage which current of air moves past said orifice and between it and the blast of air, and the coal, under the influence of gravity and suction, drops into a stream of air of double strata, one stratum of which moves more slowly than the other, so that mixing occurs in the conduit; said orifice being a hole through the bottom wall of the hopper.

4. In combination, a pulverized coal hopper having a bottom discharge orifice, a laterally extending conduit into the upper part of which {ii-e orifice opens ata point intermediate the ends thereof, a burner at one end of the conduit. means for supplying a blast of air into the opposite end of the conduit in the lower part thereof, a passage in the upper part of said conduit at said opposite end thereof, said passage being open to the atmosphere at one end and having its opposite discharge end in proximity to said oritice, whereby th said blast of air draws a current of air through said passage which current of air moves past said orifice and between it and the blast of air, and the coal, under the influence of gravity and suction, drops into a stream of air of double strata, one stratum of which moves more slowly than the other, so that mixing occurs in the conduit; and means whereby the location of the discharge end of said passage in relation to the orifice may be adjusted.

In testimony whereof I affix my signature.

CHARLES M. BUCK. 

